Do you run faster after having a baby?

This is a blog that I’ve been intending to write for a long time. While I was pregnant, many people told me that I would run faster post-baby. I knew about the rumours of Olympic athletes in former East Germany and the Soviet Union becoming pregnant on purpose during Olympic years in order to gain a fitness boost from the pregnancy. I’ve watched many of my close friends run faster after a baby. The whole running community watched running icons like Paula Radcliffe (GBR), Kara Goucher (USA) and Mary Keitany (KEN) set new records post-baby.

After my daughter was born in April, 2012, I waited for this happen for me. I told a lot of people that women run faster after they have babies. I waited awhile. And then it started happening.

Then I sat down to write this blog. I planned to do a very quick amount of google-research so that I could tell you the cold, hard facts behind the post-baby fitness boom. My google-research surprised me.

My search initially yielded an endless list of very loose postpartum exercise guidelines for women who are not serious athletes. It was frustrating to have search after search flood my screen with this insufficient information. Most of the guidelines stated to return to exercise gradually. The suggested timeline for this return varied widely from 6 weeks to more than 3 months.

Finding out exactly what it is that gives moms a fitness boost post-baby took a lot of digging.

And when my digging was complete, imagine my surprise to learn that there are no hard and fast facts about postpartum performance enhancement published because there are no hard and fast facts.

There are a few postpartum physiologic changes that are recognized as fact. There are some anecdotal reports from the world running community. There is a qualitative study. There is a guy working really hard in a Michigan sports performance lab. There are my personal friends. And there is my own experience. So let’s discuss.

First, news from the world of awesome runners.

Paula Radcliffe won the 2007 ING New York City marathon in 2:23:09 a mere nine months after giving birth to her daughter, Isla. After her win, she stated “I think your body is just a little bit stronger after pregnancy.”

Kara Goucher ran an almost 60 second personal best of 2:24:52 at the 2011 Boston Marathon, seven months after giving birth to her son, Colton.

Kenyan Mary Keitany broke the half-marathon world championship record just 15 months after giving birth to her son, Jared. Let that sink in for a second. Not only did she set a personal best, she became the fastest woman to run 21.1km on the planet.

Now onto my running friends.

My girl Shauna ran her half marathon PB during her third half marathon, only eight months after the birth of her first son. She continues to set PBs with four boys age six and under at home, including 2 year old twins. This month, she ran back-to-back 1st and 2nd age group finishes in the 10km. She was second overall female in the first.

My girl Sarah won the Valley Harvest Half Marathon this fall with a smokin’ time of 1:30:14. Her second son was 5 months old on race day. She followed this up with a second place performance at the Fredericton Marathon this month after leading the women’s field for most of the race.

My girl Tonya ran her first Boston Marathon in 2011. Her third baby was 8 months old on this April race day. We called Tonya our very own Kara Goucher as 2011 was also Kara’s comeback race post-baby.

Tonya qualified for her second Boston Marathon in Philadelphia this fall. Her fourth child was 5 months old on race day. This means she completed a full marathon training cycle 5 months after the birth of her fourth baby and nailed her BQ time with a six year old, a four year old, a two year old and an infant at home.

Me

My exposure to my running friends filled me with hope about my own return to running. I ran up until week 33.5 of pregnancy before choosing to hang up my sneakers (read more here). I was still doing track workouts with my group and coach until the track got buried in snow in January, the 6th month of my pregnancy. I often thought about how those intervals were training for my post-baby half marathon comeback race.

My comeback was quick and steady in terms of days spent running but slower than I optimistically expected in terms of performance.

I had permission to begin running 3 weeks postpartum. When my daughter was 4 weeks old, I ran the 2012 Blue Nose 5km with Team Love4Gambia. I survived in 28:xx.

I continued running regularly and rejoined my track group in July. I ran a few tune-up races. In August, four months post-baby I ran the Navy 5km, in 21:44. This was almost 2 minutes off my PB. In September, five months post-baby I ran the Maritime Race Weekend 10km, in 44:52. This was almost 3 minutes off my PB.

I continued to run 4-5 days per week. The PEI half marathon was my goal fall race. Race day arrived amidst one of the worst stretches of sleeplessness my then-six month old daughter and I went through. I barely survived a 1:42 half marathon without stopping to nap under a tree. I was proud of my effort. Proud that I had made it to the start with a gorgeous healthy baby cheering with her aunt and Nana. I chose not to be disappointed in my result because I had a daughter to set a good example for: you can’t be disappointed in an athletic event when you tried your best.

While I wasn’t disappointed, I couldn’t understand how Shauna, Sarah and Tonya were doing it. Sarah had won the Valley the week before and her baby was younger than mine. Tonya was putting in full marathon mileage while I was barely getting by with 50km weeks. Shauna was always a running wonder with FOUR kids and I had just this one.

One night at track, while lamenting these above facts, my wise friend Norma pointed out, “Don’t forget you are doing this for the first time. They (Sarah, Tonya and Shauna) aren’t.”

I don’t know how she knew that this was exactly what I needed to hear but it was.

I kept training. Five days per week. A workout with Cliff. A workout on the treadmill. Two recovery runs, usually with my daughter in the stroller. One long run.

In January, I did a VO2 max workout (fastest, hardest workout) of 1km repeats at 4:00/km. Cliff told me that he thought that my threshold workout pace (pace at which you could run for one hour) would be close to 4:00/km by the spring. I didn’t believe him.

And then it happened.

I toed the line at the March Back 2 Basics 8 miler with permission from Cliff to just giv’er. This is what happened. And what has continued to happen.

8 miler

Previous PB- 55:53 (2011)

March 2013- 53:09 (10.5 months post-baby)

5km

Previous PB- 20:09 (2010)

April 2013- 19:09 (just under12 months post-baby)

Half Marathon

Previous PB- 1:33:04 (2010)

May 2012- 1:29:54 (12.5 months post-baby)

Now back to the reasons why you run faster after having a baby.

Training through (a healthy) pregnancy is obviously known to decrease the time it takes to achieve peak athletic performance postpartum.

Changes in the Heart: VO2 Max & Cardiac Output

One of the few research studies published on this topic focuses on VO2 Max improvement. VO2 Max is the maximum capacity of an individual’s body to transport and use oxygen during intense exercise, which reflects the physical fitness or aerobic endurance of the individual.

Researchers Clapp and Capeless (1991) showed that well-conditioned women who maintained a moderate- to high-level of exercise regimen during and after pregnancy had a small but significant increase in VO2max following pregnancy.

This increase in VO2max was evident 12-20 weeks postpartum and was maintained at the time of final testing 36-44 weeks postpartum.

Another Clapp and Capeless study (1997) on pregnant athletes showed that they developed a substantial increase in cardiac output throughout pregnancy. Cardiac output is the volume of blood being pumped by the heart in the time interval of one minute.

This is logical as during pregnancy, the heart needs to pump for additional weight. In this study, the increase in cardiac output did not return to prepregnancy levels for at least 1 year postpartum. This means that the postpartum athlete’s heart pumps more blood to oxygenate running muscles with each heartbeat.

Other Physiologic Changes

James Pivarnik is a professor of kinesiology and epidemiology at MichiganStateUniversity. Most of the solid evidence comes from his research on athletes, including distance runners, during and after pregnancy at his Human Energy Research Laboratory.

Pivranik’s work has found that certain factors, such as a 60 percent increase in blood volume during pregnancy (meaning there’s extra blood to carry oxygen to depleted muscles) and a strengthened musculoskeletal system due to the progressive weight gain during pregnancy could, in theory, provide a boost to post-partum runners. But those affects are fleeting, he says, usually lasting no more than four to eight weeks after a woman gives birth.

Pivarnik’s research shows that physiologically, if there’s any advantage, it’s probably done in two months. He believes that there is a lasting change in mental strength.

“It’s not physiological as much as, ‘I’ll show them.’ ” says Pivarnik.

My Theories

So what do we have? No definitive physiological formula that accounts for performance enhancement but a theory that there is a performance enhancing change in mental strength.

In no particular order, here are my theories about what made a difference to me with my performance improvement.

Physiologic changes: Yes, I benefited as listed from a greater cardiac output and improved VO2 Max. Cliff tells me that my form has improved and become more flexible and open. I believe that this is due to the effects of the pregnancy hormone relaxin (which relaxes tendons and joints). I believe that while I was training through pregnancy, it changed my running gait in a way that I was able to maintain after the birth of my baby (relaxin production stops at birth).

The physiologic adaptation to the weight gain and a strengthened musculoskeletal system: I gained 26 lbs during my pregnancy and also ran through most of this weight gain. People often asked me if I felt heavy. Because the weight gain was so gradual, I never felt heavy while running. In fact, it was the only time I felt like my natural light self.

Although Pivarnik states that this effect is limited to the first eight weeks after birth, I wonder if because I began running so early postpartum, I was able to hold onto some of this developed strength.

Dealing with fatigue: My supportive husband has a standing appointment to leave work early on Thursdays so he can be with our daughter while I go to the track to train with Cliff and group. During the early Thursdays of my return to running, I would drive down there and fantasize about staying in the car to nap instead of getting out to run fast. Such is the fatigue of the early days of motherhood.

A new mom quickly learns to deal with the 24/7 nature of parenting an infant and the fatigue of sleepless nights. I believe that learning to cope with this fatigue helped me deal with the fatigue experienced during long distance running and high intensity track workouts.

The stroller: I often do two to three runs per week with my daughter in the BOB baby jogger. I can run as long as 14km with her. We live at the top of the city and every run ends with a long uphill climb. My daughter currently weighs 21 lbs and the stroller weighs more. I’ve gained lots of strength from running while pushing her.

What “hard” means: Your definition of what’s hard changes after natural childbirth. The pain of the late kilometres of a race are nothing compared to labour, no matter what the race distance. I respond really well to that reminder while racing. My daughter was born in less than 10 minutes of pushing and I remind myself of this with 10 minutes to go in each race: “I birthed a baby in 10 minutes, I can sure as hell run hard for 10 minutes.”

Time to train: In Canada we enjoy a 12 month maternity leave and my leave was very good to be in terms of time to train. My daughter loved to run in the stroller. She was a solid and consistent napper and I could easily spend a morning nap doing a 75 minute workout on my treadmill. My weekend long run doubled as social time with Shauna, Tonya and Sarah.

And as my coach Cliff reminds me when I try to pass off my fitness as secondary to having a baby, I put the work in.

So there you have it, an essay on running post-baby. Have you enjoyed a training boost after a baby? Let me know what you think made it happen!